SECTION 05531

GRATINGS AND FLOOR PLATES

PART 1 GENERAL

SECTION INCLUDES

Formed metal [floor] [mezzanine] [stair tread] [________] gratings.

Flat surface [floor] [stair tread] plating.

[Perimeter closure.]

PRODUCTS FURNISHED BUT NOT INSTALLED UNDER THIS SECTION

Section [______-____________]: Placement of [grating frames] [________] in [concrete.] [________.]

RELATED SECTIONS

Section [______-____________]:	Framed concrete opening.

Section [______-____________]:	Framed steel opening.

Section 02607 - Manholes and Covers.

Section 02722 - Site Storm Sewerage Systems.

Section 05500 - Metal Fabrications.

Section 05510 - Metal Stairs: Framing for grating [and stair treads].

Section 05805 - Expansion Joint Assemblies.

Section 09900 - Painting: Field paint finish.

REFERENCES

ANSI/AWS A2.4 - Standard Symbols for Welding, Brazing and Nondestructive Examination.

ANSI/AWS D1.1 - Structural Welding Code, Steel.

ANSI/NAAMM MBG 531 - Metal Bar Grating Manual.

ANSI/NAAMM MBG 532 - Heavy Duty Metal Bar Grating Manual.

ASTM A36 - Structural Steel.

ASTM A123 - Zinc (Hot-Dip Galvanized) Coating on Iron and Steel Products.

ASTM A510 - General Requirements for Wire Rods and Course Round Wire, Carbon Steel.

ASTM A525 - General Requirements for Steel Sheet, Zinc- Coated (Galvanized) by the Hot-Dip Process.

ASTM A569 - Steel,Carbon (0.15 Maximum, Percent), Hot- Rolled Sheet and Strip Commercial Quality.

ASTM B210 - Aluminum and Aluminum-Alloy Drawn Seamless Tubes.

ASTM B221 - Aluminum and Aluminum-Alloy Extruded Bars, Rods, Wire, Shapes, and Tubes.

Steel Structures Painting Council (SSPC) - Steel Structures Painting Manual.

PERFORMANCE REQUIREMENTS

Conform to [applicable] [________] code for applicable loads.

****** [OR] ******

Load Design:	[ANSI/NAAMM MGB 531] [ANSI/NAAMM MBG 532] [________].

****** [OR] ******

Design Live (Pedestrian) Load: Uniform load of [100] [____] lb/sq ft ([4.7] [____] KPa) minimum; concentrated load of [300] [____] lbs ([1330] [____] N).

****** [OR] ******

Design Live (Light Vehicle) Load: Uniform load of [500] [____] lb/sq ft ([23.5] [____] KPa) minimum; concentrated load of [2000] [____] lbs ([4440] [____] N).

Maximum Allowable Deflection Under Live Load: [1/240] [1/120] [____]; size components by [single] [double] [triple] support design.

Maximum Spacing Between Bars: To restrict pedestrian shoe heels.

SUBMITTALS

Submit under provisions of Section [01300.] [________.]

Shop Drawings: Indicate details of component supports, [openings,] perimeter construction details, and tolerances.

[Indicate welded connections using standard ANSI/AWS A2.4 welding symbols. Indicate net weld lengths.]

Product Data: Provide span and deflection tables.

Samples:	Submit [two] [_______] samples, [____x____] inch ([____x____] mm) in size illustrating surface finish, color, and texture.

Manufacturer's Installation Instructions: Indicate special requirements of [opening,] [perimeter framing,] [and] [________].

QUALIFICATIONS

Design [gratings] [and] [plates] under direct supervision of a Professional Structural Engineer experienced in design of this work and licensed [at the place where the Project is located] [in the State of [____________]].

[Welders' Certificates: Submit under provisions of Section [01300] [________], certifying welders employed on the Work, verifying AWS qualification within the previous 12 months.]

FIELD MEASUREMENTS

Verify that field measurements are as [indicated [on shop drawings].] [instructed by the manufacturer.]

COORDINATION

Coordinate work under provisions of Section [01039.] [________.]

Coordinate the work with placement of frames, tolerances for [placed frames] [openings], [and] [________].

PART 2 PRODUCTS

MANUFACTURERS

[__________________________________] Product [_________].

[__________________________________] Product [_________].

[__________________________________] Product [_________].

Substitutions: Under provisions of Section [01600.] [________.]

MATERIALS

Sheet Steel [For Die Stamping]: [ASTM A123] [ASTM A525] [________]; with [raised lug] [________] pattern.

****** [OR] ******

Formed Steel For [Pressure Locking] [Welding] [Riveting]: [ASTM A569] [ASTM A36], of [shapes indicated.] [rectangular shape.] [[________] shape.]

****** [OR] ******

Aluminum For [Pressure Locking] [Riveting]: [ASTM B221, extruded] [ASTM B210, drawn seamless tubular] aluminum alloy, of [shapes indicated.] [rectangular shape.] [[________] shape.]

Cross Bars: [ASTM B510.] [________.]

[Welding Materials: ANSI/AWS D1.1; type required for materials being welded.]

Shop and Touch-Up Primer: [SSPC 15, Type 1, red oxide] [________].

****** [OR] ******

Touch-Up Primer for Galvanized Surfaces:	[SSPC 20 [Type I Inorganic] [Type II Organic] zinc rich] [________].

ACCESSORIES

Fasteners and [Saddle Clips] [Flange Blocks] [J-Hooks]: [Galvanized steel] [Stainless steel] [Unfinished steel] [________]:

Type and Style: [________________].

Perimeter Closure:	[Of same material as grating] [________].

FABRICATION

Grating Type: ANSI/NAAMM MBG 531, [Pressure Locked] [Welded] [Riveted] [________] Type.

****** [OR] ******

Fabricate [grates] [and] [plates] [to accommodate design loads.] [to sizes indicated.]

[Mechanically clinch] [Bolt] [Weld] [Rivet] joints of intersecting metal sections.

Fabricate support framing for [openings.] [________.]

Top Surface:	[Serrated.] [Non-slip.] [Raised lug.] [________.]

Bearing Bar:	[__ x __] inch ([__ x __] mm) size, spaced [____] inches ([____] mm) on center.

Cross Bar: [__ x __] inch ([__ x __] mm) size, spaced [____] inches ([____] mm) on center.

FINISHES

Prepare surfaces to be primed in accordance with SSPC SP-[2] [____].

****** [OR] ******

Clean surfaces of rust, scale, grease, and foreign matter prior to finishing.

Do not prime surfaces in direct contact with concrete or where field welding is required.

Prime paint items with [one coat] [two coats].

****** [OR] ******

Galvanizing:	[ASTM A525 to [G90] [____] ([Z275] [____]) weight.] [ASTM A123 to [____] oz/sq ft ([____] g/sq m) weight.]

****** [OR] ******

Aluminum: [Mill] [________] finish.

Non-slip Surfacing: [Aluminum oxide.] [________.]

PART 3 EXECUTION

EXAMINATION

Verify that opening sizes and dimensional tolerances are acceptable.

Verify that [supports] [anchors] [________] are correctly positioned.

INSTALLATION

Install components in accordance with manufacturer's instructions.

Place frames in correct position, plumb and level.

Mechanically cut [galvanized] [________] finish surfaces. Do not flame cut.

Anchor by [welding.] [bolting through [saddle clips] [flange blocks].]

Set perimeter closure flush with top of grating and surrounding construction.

Secure to prevent movement.

TOLERANCES

[Conform to ANSI/NAAMM MBG 531].

Maximum Space Between Adjacent Sections:	[____] inch ([____] mm).

Maximum Variation From Top Surface Plane of Adjacent Sections: [____] inch ([____] mm)

SCHEDULES

Mezzanine: Manufactured die stamped type, serrations facing upward, galvanized steel, 200 lb/sq ft live load.

Stair Treads to Main Mezzanine: Pressure locked aluminum bars, mill finish, 75 lb/sq ft live pedestrian load.

Stair Treads to Special Mezzanine: Pressure locked aluminum bars, 1/4 x 1-1/2 main bars, 1/4 x 3/4 inch cross bars, mill finish.

END OF SECTION